Automatic evacuator for steam heating systems



Dec. 20, 1932.

E. B. TIDD AUTOMATIC EVACUATOR FOR STEAM HEATING SYSTEMS Original Filed March 20, 1931 2 Sheets-Sheet 1 wwess: v I

Dec. 20, 1932.

E. B. TlDD 1,891,483

AUTOMATIC EVACUATOR FOR STEAM HEATING SYSTEMS Original vFiled March 20, 1931 2 Sheets-Sheet 2 Patented Dec. 20, 1932 UNITED STATES PATENT OFFICE EDWIN B. TIDD, OF CHICAGO, ILLINOIS AUTOMATIC EVACUATOR FOR STEAM HEATING SYS'IEMS Application filed March 20, 1931, Serial No. 524,196. Renewed November 7, 1932.

My present invention relates to the provision of an automatic evacuator for steam heating systems, and has for its object the provision of instrumentalities for automatlcally evacuating the water of condensation and such air as is liberated from the water during the formation of steam, or otherwise finds its way, into such systems from the system, and discharges the air into the atmosphere and returns the water of condensation into the boiler. Such evacuation improves the efficiency of any steam heating system and some means of evacuating the water of condensation is necessary in systems having radiators disposed partially or wholly below the water level of the boiler.

As will hereafter be seen, I employ a vacuum secured by the condensation of steam for drawing the water of condensation and air out of the system, and I have found that in order to insure the continuing and dependable action of such a vacuum operated apparatus it is necessary to provide means for evacuating the air as it is for evacuating the water,

5 as accumulation of air in the condensation chamber prevents the formation of a sufiicient vacuum to accomplish the evacuation of the water. 7

As will also be hereafter seen, I have provided thermo-sensitive means for controlling the operation of my device, which, as employed by me, secures the delayed action or lag necessary between the successive vacuum formations to discharge the water of condensation into the boiler and to completely evacuate the air from the condensation chamber.

I have also found in the operation of such a device that it is desirable to completely open and to completely close the valve for controlling the admission of steam to the condensation chamber because if steam is permitted'to seep into the condensation chamber a balance of the transference of heat therefrom to the thermo-sensitive element may be established,

which will prevent the valve from either completely openingor completely closing, and I have therefore provided means for securing the complete opening and closing of such valve.

will also hereafter be seen, I have provided means for automatically opening a port for the evacuation of the air from the condensation chamber after the water has been returned therefrom to the boiler.

The above enumerated facilities are either necessary or highly desirable in securing the continuing automaticoperation of such a device, and I have attained the foregoing objects and results by means of the structures illustrated in the accompanying drawings, in 50 which- Fig. 1 is a schematic elevation of a boiler connected by suitable piping with radiators located below the water level in the boiler in connection with my means for evacuating the 5 water of condensation and air from such a system. I

Fig. 2 is a central vertical section through the condensation chamber and mechanism associated therewith. v

Fig. 3 is a fragmental detail to an enlarged scale of the mechanism for securing the snap action of the valve.

Fig. 4 is a perspective of one of'the sprin blades employed for securing a snap action of the valve. i

Fig. 5 is a vertical central section through V I an'automatic air relief valve. Y

Similar reference characters indicate 'simi-' lar parts throughout the respective views. v A typical steam heating systemwith which my invention is associated comprises a boiler 10 of any desired type, having one or more risers or feed pipes 11 with which are connected branches 12 leading'to radiators 13, which, for more typically illustrating my invention, I have shown located below the water line of the boiler. The radiators 13' are suitably connected with areturn 14 leading. towards the'boiler, but instead of connecting the return 14 directly with the boiler I' connect it with a chamber into which the water formed bythe condensation of steam in the system flows.

I have shown this accumulation chamber for the water of condensation as consisting of a bottom cap 15 provided with oppositely disposed tubular embossments 16 and 17. The return l l assembles with the embossment l6 and into the embossment 17 mayadvantageously be inserted a suitable drain fitting 18 for manually draining and cleaning out the system. Into the cap 15 is screwed a length of pipe 19 of sufficient diameter to secure the requisite capacity. The top of the length of piping 19 is closed by cap 20 perforated and tapped to receive the air vent 21 and perforated to permit the passage of the vertically disposed pipe 22 which extends from adjacent the bottom of the accumulation chamber through the cap 20 to adjacent the bottom compartment 23 of the condensation chamber, where it makes connection through the union 24 with the casing 25 of a ball check valve mounted in the bottom wall of the lower compartment 23 of the condensation chamber. The ball check valve casing 25 is similar to such constructions in having a constricted passageway 26 above the restriction in which a ball 26a seats by gravity and the weight of such liquid as may be present above the ball, but my checkvalve differs from the ordinary check valve in having the ball containing portion thereof closed by the mesh or reticulated cap 27 and inhaving pivoted on the wall thereof the angledlevcr 28, one arm whereof extends down beside the ball in position to move it from its seat, and the other arm whereofextends away from the check valve casing and has provided on the end thereof a float 29. The lever 28 is so angled and proportioned that the ball is unseated when the float is resting on the bottom of the lower compartment 23 of the condensation chamber.

' Also communicating with and extending from the bottom of the lower compartment 23 of the condensation chamber is a run'of piping 30 in which is interposed a check valve 31 leading to ,andcommunicating with the boiler 10 below the water level thereof. The piping 30 is of such length as to bring the lower compartment 23 of the condensation chamber well above the water line in the boiler 10.

' Rising from one side of and having com,- munication with the lower compartment 23 of the condensation chamber is the upper compartment 32 of the condensation chamber which communicates through the elbow33 in the top thereof and nipple 34 with the T- shaped casing 35 constituting a portion of a needle valve. Into the lower arm of the T-sha-ped casing 35 screws a packing gland 36 for the stem 37 of the needle valve, and into the opposite arm of the T-shape d casing 35 screws the needle valveseat 38 and a nipple 39 connecting with the T 40, one end whereof is closed with'a plug 41 and the other end whereof communicates through tubing 42 with the steam chest of the boiler 10, or. as is shown in Fig. 1, with the riser or feed pipe 11.

- It may be said at this point that strainers may advantageously be employed in connection with the cap 15 of the accumulation chamber and of the T 40 to exclude rust and other sediment from the condensation chambers and the mechanism associated therewith.

There may also be included in the tubing 42 a manually operated valve so that steam may be excluded fromthe evacuator when inspection or adjustment is desired.

Arising from the top of the lower compartment 23 beside the upper compartment 32 of the condensation chamber are a pair of spaced columns or rods 44, the upper ends whereof are secured together by aplate 45, through the center of which extends the packing gland 36 and centrally between which rods or columns 44 depends the valve stem 37.

Seated upon the top of the lower compartment. 23 of the condensation chamber between the rods or columns 44 are the thermo-sensitive elements which I have illustrated as-consisting of the concentrically corrugated and embossed hollow disks 46, which disks contain a liquid selected so-that it will volatilize at a predetermined temperature, say at or around 212 Fahrenheit, and expand the disks laterally. Such disks arenow manu factured and are to be obtained in the market, and their particular construction constitutes no portion of my invention.

Seated upon the topmost thermo-sensitive disk 46 is a disk or washer 47 centrally bored and tapped and into which is screwed atappet rod 48 aligning with and extending up.- wardly to adjacent the bottom of the 'valve stem'37. The rods or columns 44 may conveniently be each formed of lower members 44a and upper members 446 having their adjacent ends threaded and connected by a cou-, pling 49. A coiled-expansion spring 50 seating on the disk or washer 47 extends upwardly therefrom into cooperation with a'plate 51 perforatedfor the passage of the columns. or rods 44 and the tappet 48. The plate 51 is held against the actionof the spring 50 by the couplings 49 and by means of the adjustment of the couplings 49 the tension upon the spring 50 may be adjusted to secure the conditions hereinafter described.

The lower end of the valve stem 37 and the upper end of the tappet 48 are provided with I coupling 53 and entering these cross slots and extending therebetween are spring plates 55 of slightly greater length than the horizontal distance between the coupling 53 and the rods 44. The plates55 are so proportioned and located'thatwhen they are in their upward position they will seat or assist in seating the valve 37 in the valve seat 38, and when they are in their lower position they will secure or assist in securing the adjusted open position 5 of the "alve 37.

When the thermo-sensitive disks 36 expand under the influence of the heat, suflicient power is developed to overcome the action of the spring and the spring plates until the coupling 53 is forced upwardly past the horizontal plane of the plates55 when the spring plates operate to immediately com pletely seat the valve 37. To permit such action by the spring plates 5 55 the headed ends of the valve stem 37 .and tappet 48 are so spaced in the coupling 53 that the plates 55 may accomplish this throw Without putting any additional strain upon the spring 50. The tension on thespring 50 is so adjusted by the adjustment of theposition of the plate 51 that when the thermo-' sensitive elements 46 cool off and retract the force of the spring 50 will be sutficient' to carry the inner ends of the plates 55 below their horizontal planes, in which position the combined action of the plates 55 and the spring 50 will be effective for fully opening the valve 37.

The air vent 21, heretofore described as mounted in the upper cap 20 of the accumulation chamber, is a piece of mechanism well known and to be obtained in the market, but is here described in order to more completely explain the operation of my invention. This air vent 21 consists of a hollow base 21a upon which is mounted a thermo-sensitive disk 21?) above which is a float 21c terminating at its top in a valve nipple 21d. Surrounding the therino-sensitive element and the float is a casing 216 in the top of which is aport 21f closed by the valve nipple if the disk 21b expands or water enters the casing and raises the float. The upper entrance to the valve port 21; is closed by a ball valve 219.

It will be seen that air entering from the bottom of this device under suflicient pressure to raise the ball valve 219 flows therethrough until steam orwater enters the device, which then closes through the functioning of either the thermo-sensitive element or the float and that air cannot re-enter the device from the top through the action of the ball valve.

The operation of my device is as follows:

Steam is admitted thereto by manually opening the valve 43. The thermo-sensitive elements 46 being cool and in contracted condition, the valve 48 will be in open position and steam will proceed through the nipple 32 of the condensation chamber. The flow of steam into the upper compartment 32 of the condensation chamber and from thence into the lower compartment 23 of the condensation chamber forces the air through the 34 and elbow 33 into the upper compartment check valve 25, the ball 26a of which is unseated by reason of the action ofthe lever28. Even upon the first operation of my device the amount of air which flows into the piping 30 is not suflicient to interfere with, although it probably slightly impairs the efficiency of, its operation. After the first cycle of operations the piping 30 will be filled with water and will no longer be capable of furnishing air to the condensation chamber. The air is forced downwardly through the pipe 22 and through such water of condensation as may have accumulated in the accumulation chamber and is forced through the air relief'valve 21 into the atmosphere. In the practical operation of my device steam just begins to reach the water of condensation in the accumulation chamber whenthe' thermosensitiveelements 46 are sufliciently heated to expand and close the valve48. Heat dissipates rapidly from the condensation chamher and the vacuum formed therebyin this chamber sucks upthe contents of the accumulation chamber and its connected piping through the pipe 22 into the condensation chamber. 1 The water thus brought into the condensation chamber raises the float 29 and 7 permits the seatingof the ball 26a, preventing the return of the water through the pipe 7 22 to the accumulation chamber. The inrush of the water'into the condensation chamber assists in cooling" the. thermo-sensitive elements 46 and the valve 48 is opened through the action of the springs .50'and 55. This equalizes the pressure in the topof the condensation chambers with the pressure of water in theboiler and in the'tubing 30 connected with the boiler and the weight of the water in the condensation chamber drains it through the piping 30 and check valve'31 back into the boiler until the lower compartment 23 of the condensation chamber is emptied, when the check valve 25 is opened and such air as may remain in the condensation chamber is evacuated through the pipe 22. The condensation chamber being again filled with steam, the thermo-sensitive elements-are again heated and the cycle of operations is repeated.

WVith an embodiment of my invention capable of evacuating two quarts of water in one cycle of operations, andoworking ata steam pressure of two pounds, Ihave found that an entire cycle of operations occurred in approximately four minutes. .Such time,

I have found that the liberation of air from the water in the boiling thereof, or the leakage of ai r into an ordinary steam heating system is such as to require the means provided by me, or some other equally eflicient means for evacuating the. air-from. the system in tion chamber, a check valve for preventing order to insure thev dependable automatic operation of my evacuator.

It will further be seen that, where a steam supply is available my evacuator may be employed for evacuating other than steam heating systems by connecting the accumulation chamber with the locality to be drained and the piping 30 with the locality where the water is to be discharged.

. Having described my invention What I claim as new and desire to secure by Letters Patent is: V

a 1. A device of the kind described, comprising a condensation chamber, thermo-sensitive means controlling the admission of steam tosaid condensation chamber, a plurality of conduits leading from said condensation chamber, one of which conduits is provided with means for preventing a back flovvtherethrough and a float actuated valve for. controlling the discharge through the other of said conduits.

2. A device of the kind described, comprising a condensation chamber, thermo-sensitive means controlling the admission. of steam to said condensation chamber, a pluralityof conduits leading from the bottom of said condensation chamber, :one of which conduits is provided with means for preventing a back flow therethrough and the other of said conduits being provided with means to prevent a discharge therethrough and means controlled by the liquid content of said condensation chamber for opening said. last mentioned means.

3. A device of the kind described, comprising a condensation chamber, means 'forintermittently admitting steam to said condensation chamber,a plurality of conduits leading from the bottom of said condensation chamber, one of which conduits is provided with means for preventing a back flow therethrough, and the other of said'conduits being provided with means 'to prevent a discharge therethrough and means con.- trolled by the liquid content of said condensation chamber for opening said last mentioned means.

4. A device of the kind described, comprising a condensation ChitIIlbGl',-th8lIIlQ-S6Il sitive means controlling the admission of steam to said condensation chamber, a plurality of conduits leading from the bottom of said condensation chamber, a check valvefor preventing a back flow in one of said conduits, a check valve for preventing a flow into the other of said conduits and a float actuated mechanism for opening said las mentioned check' valve. 1

5. A device of the kind described, comprising a condensation chamber, means for intermittently admitting steam to said condensation chamber, a plurality of conduits leading from the bottom of said condensaa back flow in one of said conduits, 'a check valve for preventing a flow into the other of said conduits and a float actuated mechanlsm for opening said last mentioned check valve. 1

6. A device of the kind described, compris- 1ng a condensation chamber, thermo-sensitive means controlling the admission of steam to said condensation chamber, a plurality of conduits leading from the bottom of said condensation .chamber, a check valve for preventing a back flow in one of said conduits, a

check valve for preventing a flow into the other of said conduitsjand a float actuated mechanism for opening said last. mentioned check valve and an accumulation chamber with the bottom of which said last mentioned discharge conduit communicates and an automatic air relief valve communicating with the top of said accumulation chamber.

v7. In a deviceof the kind described, a condensation chamber, a discharge conduit leading therefrom,means for preventing a back flow in said discharge conduit, an inlet conduit communicating with said condensation chamber, means for preventing an outward flow: through-said inlet conduit, means operated by the liquid content of said condensation chamber for opening said last mentioned means, said condensation chamber having a port for the admission of steam thereto, a valve controlling said port, thermo-sensitive meansfor closing said valve and a spring for opening saidvalve.

8. A device of the kind described, including a condensation chamber, a port for admitting steam to said condensation chamber, a valve controlling said port, thermo-sensitive means for closing said valve, avspring for opening said valve and means associated with said last mentioned spring for snap-ping said valve into opened and closed position.

9. A device of the kind described, including a condensation chamber, a port for admitting. steamto said condensation chamber, a valve having a stem controlling said port, means actuated by the steam for intermittently opening and closing said valve, and means actuated by the movement of said valve and stem for snapping said valve into fully opened and closed position.

.10. In a device of the kind described, including a condensation chamber having a port controlled for the discharge of liquid therefroimand a port controlled for the entry of liquid thereto, automatic means for opening said last mentioned port, an accumulation chamber, said last mentioned port communicating withthe bottom of said accumulation chamber whereby air entering said accumulation chamber will be trapped from re-entry into the condensation chamber by the liquid accumulated in said accumulation chamber.

11. A device of the kind described, including a condensation chamber having a port for the introduction of steam thereto and a port for the discharge of liquid therefrom and having another port for the discharge of air therefrom and the induction of liquid thereto, and means for closing said last mentioned port until the liquid has been discharged from the chamber.

12. A device of the kind described including a condensation chamber, a port for admitting steam to said condensation chamber, a valve controlling said port, means for intermittently opening and closing said valve, and means actuated by the movement of said valve for snapping said valve into fully opened and closed position.

EDWIN B. T1131). 

